That is amazing, but every one of those frames is hand-painted. That scene is 94 seconds long, so that’d be 2,253 frames. 2,253 frames x 30 mins animation etc. per frame = 67,590 minutes. Which is 1,127 hours or just under 47 days.

In other words, that scene alone would’ve taken just under 47 days of animator time to produce¹. There’s no way CGI would take that long. A comparable scene with CGI would take a day or two of animator time. Big, big difference.

1. Of course, multiple animators worked on it. The actual scene probably took a week or so to make once filming and editing was complete.